Refrigerator window



Oct. 8. 1940. R. M. RQBINSQN REFRIGERATUR WINDOW Fild March 8, 1940iatenteduoct. 8,Y 1940 I l t l UNITED STATES PATENT j oFFicEREFBIGERATOR WINDOW Robert M. Robinson, Philadelphia, Pa., assignmoione-half to Noar Klein, Philadelphia, Pa.

`Application March 8, 1940, Serial No. 322,901

12 Claims. (Cl. 62-89.5)

This invention relates to refrigerator windows, a condenser for aircirculating purposes; and Mld- Paltcula'rly t0 Ineens t0 Preventcondensamany other objects and advantages will become tion oi' moistureon the surfaces of the panes more apparent as the description proceeds.comprising such windows; In the accompanying drawing:

Owing to changes of volume of air entrapped Fig. 1 represents afragmentary vertical secg between spaced panes in Windows ofrefrigerator tion through a window and through the associated show casesand the like, incident 'to variations of moisture condenser element,showing the circutemperatures imposed upon the windows, both latingstream by arrows; inside and outside of the case, leakage about the Fig.2 represents a diagrammatic perspective edges of the /panes isinevitable, so thateven if of the several spaced panes and the channelsand m the initial c rge of entrapped airis dehydrated, conduitsassociated therewith showing thecircuan event pumping action replacesthis with lation by arrows; .Y moisture-laden atmosphere, and eventuallythe Fig, 3 represents a vertical section through the moisture content issuch as to cause condensation moisture condensing unit for the window.

- onfthe cold window panes. Many efforts have In carrying out theinvention in a preferred 15 been made inthe past. to cure this tendency,as form a metallic moisturecondensing device is arby providing areservoir of dehydrating material ranged to be chilled by the internaltemperatures to absorb the moisture. either by direct contact in the boxcontaining the window, and communiwith the spaces between the panes, orby forrncates at the bottom through the innermost pane l ing amechanically actuated closedcircuit of the window, and channelsareprovided through 20 through the space betweenthe panes and a detheother panes to an upper outlet passage leadliquescent agent, or thelike. `These expedients ing into the top of the condenser. The naturalare expensive to build and to service and are of thermal circulationthus secured travelling down- ,relatively short life. 'I'he advent ofthe low temward through the moisture condenser, laterally perature caseadapted to preserve frozen foods, f and longitudinally in series owthrough the sevhas complicated the situation and exposed theineralispaces between panes and return into the adequacies of presentcondensation preventing top oi' the condenser will be augmented, ifnecesmethods. sary, by a relatively small heating unit in the It isamong the objects of this: invention: to front space of the window,having the dual funcso improve the Window construction of show casestion of gently warming the glass to prevent ex- 3 and the like; toutilize the natural periodic cyclic ternal condensation thereon, andalso imparting variation of temperatures oi? the refrigerator for energyto the closed circulation.

maintaining the windows free from condensed The details of therefrigerator proper or other moisture; to adapt the natural lawsaffecting the window containing device will naturally vary ac- 85 aircurrents, and air circulation to prevent conasvcomprising a front wallI0, the window Il, to densation of moisture on the panes of the winbedescribed, sealed at'the top, bottom and sides dow; to provide asubstantially closed circulating as far as practicable, asis common withwindows system for the spaces between panes of a Window; of this type,and at the top merges into the slopto provide with a circulatingl systemfor air being or slanting insulating front wall 20, connected phenomenaof relative humidity, convection of cording to demands, but may begenerally set out 36 tween spaced window panesmeans for extractbyinsulating top wall 2l, to insulating rear wall 4 ing moisturetherefrom; to eliminate or sharply 22. The refrigerator compartment orcabinet minimize the chances of deposit of dust, films, space 23, iscompleted by suitable end insulating spoor or mold on the inner,surfaces of spaced walls 24 and lower insulating floor or sub-floor 25.window panes in a refrigerator or show case; to The "sght window throughwhich the conprovide a dehydrating system for windows which tents of thecase are observed, and whichit is is susceptible to quick, easy andcheap replaceimportant to keep clean, dry and dustless at all ment orrecharging; to provide a circulation times, may comprise a single spacebetween two through the spaces between a plurality of panes spacedgenerally parallel panes, or any addisuch circulation passing through anaperture in tional number 'of dry air spaces desired. Prefthe glass; toreduce the cost of condensation free erably and desirably, especially inview of the 5 windows; to provide aclosed circulation system insulationdemands'incident to the low temfor window spaces containing a condenserfor enperatures maintained, the window comprises four trapped moisture;to provide a novel heating parallel spaced panes respectively, I2. Il,I8 and means for accelerating an air circulation; to pro` I8, in orderoutwardly from the interior of the vide 'means for utilizing otherwisewaste heat of case. Panesiz and I4 denne a rear or inner up. |55

ward flowing space I3. Intermediate air space I5' between panes I4 andI6 comprises a generally downward flow of circulating air streamentering the said space through upper transverse bore 35 of pane I4.Front upward ow space I'I is defined by pane I Ii and front pane I8 andhas an entrance for circulating air through a low transverse bore 36 ofglass I8.

With the type of box particularly benefitted by this invention asuitable powerful freezing unit (not shown except for a fragment of thehotter end of the condensing coil thereof, at 26) is disposed below thesub-floor 25, but connected to suitable coils 2'I by which thetemperature of the compartment can be maintained at a satisfactorydegree. Illustratively only the preferred temperature is between 0 F.and 15 F. Suitable shelving and the like will be provided as may bedeemed necessary.

Preferably disposed at one side of the window so as not to obtrude uponnor obstruct the sight through the window, is the preferablysubstantially vertical cylindrical metallic condenser 28. This may be ofvarious shapes, and extend either in whole or in part horizontally aswell as Ver-l tically, if desired, and may have such external orinternal flnning and the like (not shown) as may be found desirable. Thelower end of the dehydrating tube or condenser 28 is suitably threadedor otherwise provided so as removably to receive and tightly join, aclosure cap or moisture trap or retainer 30, which may comprise a merereceptacle, or be a container of a dehydrating element such as calciumchloride, silica gell, or the like. At a slight distance above the upperend of the closure cap 30, an intake or inlet tube 3| extends generallyradially of the cylinder 28, or .parallel to a radius, through a bentconnection, to sealed entrance through a small bore or aperture 32formed in the inner pane of glass I2 toward its lower end and near onehorizontal end thereof. The upper end of the condenser cylinder 28communicates with a suitably disposed and bent conduit 33 partiallywithin the chamber 23, and partially within the insulation of the frontwall 28, and the latter preferably extends within the upper frame of thewindow the full length of the window in space I1 to communicationthrough an exhaust port 34 with said front space I1 at the far end,horizontally, away from the intake 3|, and vertically spaced from samealso, as it is disposed at the top of the window.

To facilitate and direct flow between the several panes in series, aspreviously noted, the rear complemental' pane I4 is drilled at 35 inclose proximity to the upper edge to form a passage between the spacesI3 and I5, this passage 35 entering the space I3 at the opposite endfrom the bore 32 in the pane I2. The transverse duct or bore 36 in paneI6 establishing communication between spaces I5 and I1 is generallylaterally alined with the bore 32 in pane I 2.

It will be clear that window I2 is always the coldest, and thatprogressing toward the front the respective panes will become graduallywarmer, until the very front pane I8 will be somewhat less than that ofthe atmosphere surrounding the case. It will also be clear that with thecylinder 28 made of thin metal such as of copper or metal of likeconductivity, it will be chilled by the very low temperature in the caseso that air coming downwardly into it will be at a lower temperature atthe lower end than comes in at the upper end, so that the air will startto descend withinthe condenser as a local conflned convection current,and at the same time owing tothe extremely low temperature of the wallof the condenser any moisture carried by the descending air will bedeposited as either frost or moisture on'the walls of the tube 28. Thedehydratedalr with its initial fall and establishment of a descendingcurrent will pass laterally out of the condenser and through bore 32into space I3 between the panes I2 and I4. Owing to the slight pressurebehind it, and also to the fact that a slight suction is being exertedupon it for the purpose (as will be pointed out) the air moves in spaceI3 longitudinally and upwardly, sweeping between the glasses, until itpasses through bore 35 into the upper part of channel or space I5, inwhich it sweeps downwardly and longitudinally and through low bore 36,pursuant to which it sweeps longitudinally and upwardly from the lowerpart of space I'I, to the exhaust bore or aperture 34, into the pipe 33,in which itl runs initially longitudinally of the space I'I, and fromwhich it runs rearwardly into the top of the cylinder 28, and the cycleis complete. The series circulation thus established is definitelyfacilitated and augmented by the fact that the front pane is warm enoughto impart energy to the circulation, and thus to create suction on thecircuitous channel just described. To this end the conduit 33 may beinsulated until after it empties into the condenser 28, to help maintaina circulation'.

In this latter connection, it is contemplated that an auxiliary sourceof heat may be provided, preferably within the front space I1, such asan electric resistance unit or small wire or the like lying in the lowerpart of the space, or by providing the heat circulating pipe 38 lying inthe bottom of the space I'I, and having a substantially vertical portiondisposed in close proximity to the hot portion of the condenser of thefreezing unit, so as to establish a closed confined convection currentwithin the pipe 38. Obviously the warmed air rises in the pipe 38, givesup its heated energy in the space I'I, and descends out of the far endof the space I'I as a descending cooled air stream, to maintain thecirculation. This heat energy imparted to the air in the space II causesan acceleration of the upward flow and its exhaust into the upper end ofthe condenser tube 28.

In order to minimize the break-down of the sealing insulation about theedges of the panes it is important to maintain the circulatingdehydrated air stream passing through the window at a pressure whichdoes not depart from atmospheric by any but the smallest quantities.This may be easily and cheaply accomplished by providing a minute pinhole 40 at the bend of the pipe 33 as it enters the tube 28. If desireda delicate valve mechanism can be associated therewith so as to respondto inner and outer diiferential pressures of a magnitude less than thatwhich will break down the insulating seal of the panes. However, ingeneral the minute aperture 48 will possess such frictional coemcient onair passing throughit, that it is easier for the syphon action (so tospeak)l of the incoming warm air entering the condenser tube, while thevdescending cooled air stream exerts suction to pull the warm airthrough and down, than it will be for the suction or partial vacuum tobe released or satisfied with the air entering the pin hole 40.Particularly is this true when the acceleration of the upward flow inthe front space 5 circulation.4

defrosting stages in the cycle of operationof the unit of the show case,and as the temperature inthe caseisallowedtorisetomeitthefrost on` coils21.v a similar result will be derived from the warmed condenser'tube 1l,so that the frost on its` inner surface will be melted and will run downand be collected in the cup .Il at the bottom of the tube. As thetemperature is again lowered, any moisturel that might have been pickedup by the circulating window stream is ycarried through "until it isre-deposited internally of the tube Il. It will be understood that thedew-point of the air leaving the bottom of tube 2l is always lower thanthat attaching to any of the panes of the window, so that nocondensation on the inner surfaces oi.' the panes can occur.

The cheapness. efiiciency and minimized service requirements devolvingupon the use of the invention will be evident, as will the fact thatmany changes can be made in the' invention'withoutV .detracting from itsscopeand without avoiding `the terms Voi' the appended claims. Obviouslythe circulation canpassthrough suitable apertures inthe frame in placeofthrough bores formed in the glass. 4

I claim as my invention: l. In refrigerator windows, a plurality ofspaced panes defining a plurality of' spaces between the with theadjacent space between panes, conduit means extending from the upper endpf the tube and communicating with another space between panes, andmeans establishing communication between the said two mentioned spacesbetween panes. l l 2. v In refrigerator windows, a plurality of spacedpanes defining a plurality of -spaces between the panes, a closedmetallic condensing tube having vertically spaced ends, conduit meansextending i from the lower end of the tube to communicate with theadjacent space between panes, conduit means extending from the upper endof the tube and communicating with another space between panes, andmeans establishing communication between the said two ymentioned spacesbetween panes, said last mentioned means comprising a bore through apane.

3. In refrigerator windows, a plurality of spaced panes defining aplurality of spaces between the i panes, a closed metallic condensingtube having vertically spaced ends, conduit means extending from thelower end of the tube tocommunicate with theA adjacent space betweenpanes, conduit means extending from the upper end of the tube andcommunicating with another space between panes, and means establishingcommunication between the said two mentioned spaces between panes, andmeans for introducing heat energy into the space between the panesconnected to the i conduit leading to the top of said tube.

, sealed to said conduits to complete a closed circulatory path, andmeans for chilling the condenser to dehydrate the circulating air, and aminute aperture communicating with said condenserto permit relativeexpansion and contraction of the circulating air'without stopping the iaudace 5. In refrigerator windows, a plurality of spaced air spaces. acondensing tube comprising a thin panes'establishing, a..plurality ofcommunicating l wall metallictube the ends of which are at differentlevels, means establishing communication from the respective ievelsvofthe tube through a window space between panes, and said cap containingdehydrating material. l

6. In refrigerators, means defining a refrigeratorcompartmentjandincluding a. window, means including a condenser forlowering the 'temperature in the compartment, said window A comprising aplurality of spaced panes, means forl circulating air through the spacebetween the panes, a pipe disposed in the said space between the panesand leading to a point in such proximity to said' condenser as toconduct heat therefrom into said space to accelerate the air flowthrough Said space and to warm the adjacent panes.

7. In refrigerators, means dening a refrig.

erator -compartment and including a window, means including a condenserfor lowering the temperature in the compartment, said window comprisinga plurality of spacedpanes, means for circulating air through the spacebetween the panes, a pipe disposed in the `said space between the panesand leading to a point in such proximity to said condenser as tocond-uct heat therelfrom into said space to accelerate the air flowthrough said space and to warm the adjacent panes, and a metalliccondensing tube disposed in said compartment and maintained at lowtemperature, said means for `conducting the air comprising connectionsbetween said tube and the space between the panes. d

8. In refrigerators, means defining a refrigerator compartment andincluding a window, means including a condenser for lowering thetemperature in the compartment, said window comprising a plurality ofspaced panes, means for circulating air through the space between thepanes, a pipe disposed in the said space between the panes and leadingto a point in such proximity to said conspace to accelerate the air flowthrough said space and to warm the adjacent panes, a metallic condensingtube disposed inv said compartment and maintained at low temperature,said means for conducting the air comprising connections between saidtube and the space between the panes, and auxiliary means permittingexpansion and contraction of the pressure of the circulating air streamwithout affecting the circulation.`

9. In refrigerators, a. plurality of spaced panes defining a pluralityof spaces between panes, a closed conduit 4in such refrigerator, andmeans conducting air from said conduit in series through the spaces toreturn to the conduit.

10. In refrigerators, means defining a refrigerating compartment and awindow, a refrigerating unit in said compartment, said unit being in acooling system 'having a condenser outside of said compartment, saidwindow comprising a plurality of spaced panes forming a plurality of airspaces and having staggered bores to provide' la path for air t`o flowthrough said spaces in series,

' for dehydrating purposes, and means extracting heat from saidcondenser to warm the air in the ldenser as to conduct heat therefrominto said pane spaces and promote circulation therethrough.

11, In refrigerators, means defining a refrigerator compartment and awindow, a refrigerating unit in said compartment, said unit being in acooling system having a condenser outside of said compartment, saidwindow comprising a plurality oi' spaced panes forming a plurality ofair spaces, each pane, other than the outer pane, having a boretherethrough to form a communication between adjacent spaces, said boresbeing so located that air travels laterally and longitudinally of eachspace and in series through said,

air in one of said pane spaces to promote circulation of airtherethrough.

12. In refrigerators, means dening a refrigerator compartment and awindow, a refrigerating unit in said compartment, said window comprisinga plurality of spaced panes forming a plurality of air spaces, eachpane, other than the outer pane, having a bore therethrough to form acommunication between adjacent spaces, said bores being so located thatair travels laterally and longitudinally of each space and in series`through said spaces, and a condensing tube in said compartment havingconnections communicating respectively with the inner and outer Windowspaces.

ROBERT M. ROBINSON.

